Refactor create issue end-to-end test

What does this MR do?

This refactor:

• Moves the tests pre-conditions to before blocks
• Creates an issue via the API in the second test to improve the test suite performance.

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry for user-facing changes, or community contribution. Check the link for other scenarios.
• [-] Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content